Deformation models under intense dynamic loading (Review)

Abstract

This paper considers currently available models of irreversible deformation processes of materials under dynamic, in particular shock-wave, loading. The models can be divided into three groups: (1) macroscopic (continuum) models-traditional models of continuum mechanics, primarily classical models of elastic-plastic deformation, their various generalizations to the case of dynamic processes and models of viscoelastic relaxation media; (2) microstructural models based on the description of microstructural mechanisms of irreversible deformation (usually, the concept of the kinetics of a dislocation ensemble); (3) atomistic molecular dynamics models and calculations. A special category includes the most promising (from the point of view of the author) multilevel models which combine the advantages of each of these approaches and consider deformation mechanisms of various levels. Examples of calculations using such models are presented.

Semi-analytical modeling of steady weak shock wave front for solid metals following the Swegle–Grady relation

“…In studying the shock wave, shock wave profiles are obtained by numerical methods such as continuum models, models based on dislocation dynamics, molecular dynamics (MD), and multilevel models. 16 The most efficient method for calculating the steady weak shock wave front are the continuum models, which are based on the conservation laws and the yield function relations of the specified material. In recent years, some complicated models have been developed by use of both the continuum models and dislocation dynamics-based models to obtain the shock wave front at different levels of the applied pressures.…”

“…Various authors have used numerical methods 16 to obtain the shock wave front profile and, in this respect, Malygin et al. 11 obtained a simple low precision equation for steady strong shock waves.…”

“…Various authors have used numerical methods 16 to obtain the shock wave front profile and, in this respect, Malygin et al 11 obtained a simple low precision equation for steady strong shock waves. There are few simple models 11 for steady shock wave fronts and, therefore, representing simple high-precision relations for steady weak shock waves is the main motivation for this study.…”

Molecular-dynamic simulation of nanocrystal structure evolution under dynamic loading

“…The application of these methods permits studying the microstructural mechanisms of irreversible deformation, which is impossible for available experimental methods. As is shown in [1,2], it is the major advantage over the other methods and models of dynamic deformation. This paper presents results of the molecular-dynamic simulation and investigation of the peculiarities of the uniaxial shock (short-time) compression of copper nanocrystals.…”